Method of and a means for reducing the yarn tension on a balloon-forming twist spindle



June 25, 1963 K. NIMTZ ETAL METHOD OF AND A MEANS FOR REDUCING THE YARNTENSION ON A BALLOON-FORMING TWIST SPINDLE Filed June 13, 1960 5Sheets-Sheet I June 25. 1963 K, NlMTZ ET'AL 3,094,835

METHOD OF AND A MEANS FOR REDUCING THE YARN TENSION ON A BALLOON-FORMINGTWIST SPINDLE Filed June 13, 1960 3 Sheets-Sheet 2 2 cu l m 7/ an MD Kjigs/7802's WM 3 wwsa vw 3,094,835 13D 3 Sheets-Shee 3 June 25, 1963 K.NlMTZ ETAL METHOD OF AND A MEANS FOR REDUCING THE TENSION ON ABALLOON-FORMING TWIST SPI Filed June 15, 1960 United States Patent Thisinvention relates to a method of and means for a reducing the yarntension on any type of balloon-forming spindle, particularly on a doubletwist spindle.

If the balloon which forms during the twisting operation is given fullfreedom to expand, friction between the yarn and the air as well as theengendered centrifugal forces subject the yarn to tension. In view ofthis fact it is already the practice to provide balloon limiters withthe object of constraining the balloon and thereby preventingcentrifugal forces from increasing the tension of the yarn, or at leastof minimising their effect. Known balloon limiters have the form ofrings or of cylindrical bodies which support the yarn uniformly aroundthe entire circumference of the balloon. However, this arrangement whichhas given rise to the construction of balloon limiters of variousmodified kinds still does not exhaust every available possibility ofreducing the tension of the yarn.

It is the object of the present invention to provide a means of furtherreducing yarn tension on balloon-forming twist spindles, particularly ondouble twist spindles, where the yarn having been intercepted by thelimiter from substantially the zone where ballooning is generated tendsto balloon out to a maximum balloon diameter.

According to the invention the solution of the contemplated problemconsists in imparting kinetic impulses to the yarn directed inwardlytowards the centre of the balloon at zones distributed around theperiphery and/or axial length of the balloon. These inwardly directedimpulses impress a shape upon the balloon which, at least at the zonesof application of the said impulses, will be defined by a diameter lessthan that which corresponds with its maximum diameter. Consequently theballoon will skip from one point of impulse application to the next,traversing the intervening space more or less freely. Consequently thetotal friction will be less, resulting in a reduction of the tension ofthe yarn. Moreover, the overall size of the balloon will be constrictedso that the tension engendered by centrifugal forces will likewisediminish.

For performing this method the invention provides a balloon limiterwhich comprises at least one ring in its interior, said ring beingprovided with inwardly projecting sections. This ring may be of undularconformation. The undulations may have a saw-tooth shape. It is alsopossible to give the inside edge of the ring a polygonal shape.

Furthermore, axially adjacent rings may be arranged in such manner thattheir inwardly projecting sections are angularly equidistantlystaggered. This latter arrangement not only constricts the balloon butalso imparts a kind of wobble motion to the travelling yarn.Unexpectedly, this has likewise been found to reduce the total yarntension.

According to the invention smooth rings may also be used in place ofrings formed with inwardly projecting sections. In this alternative formof construction at least two axially spaced smooth rings which have noprojections are positioned with their centres located on an imaginaryhelix surrounding the limiter axis at a given distance therefrom. If aplurality of rings thus disposed is provided, they will likewise imparta wobble motion Ice to the ballooning yarn and thus secure the aforesaidadvantages. t

It will be readily understood that the axial length of the rings is notnecessarily very short. Rings may in fact be used which represents smallcylinder sections, in other words sleeves, or the like.

A number of preferred forms of construction of suitable rings are shownin the drawings and illustrate the present invention. In the drawings:

FIGS. 1 and 2 are plan views of balloon limiters according to theinvention,

FIG. 3 is an alternative formof construction.

FIG. 4 is a vertical axial section of the embodiment shown in FIG. '3,

FIG. 5 is a plan view of yet another form of construction, and

FIG. 6 is a vertical axial section of the embodiment shown in FIG. 5.

20 in FIG. 1 indicates the balloon limiter proper, i.e. the envelope ofthe limiter which is of smooth cylindrical shape. 21 is a ring formed onits inside periphery with inwardly projecting sections, the saidsections on the illustrated ring being undular. The inwardly projectingsections are indicated by 22 and it will be clear that when theballooning yarn strikes these elevations it will more or less skipacross the intervening recessed portions 23. The yarn therefore travelspart of its way freely suspended in space and since the points ofsupport are distributed around the periphery its actual friction bylicking the limiter proper is practically negligible. At the same timethe described arrangement constricts the external periphery of theballoon at least at the levels where constraining rings 21 have beenfitted.

The overall shape of the balloon which will now form is, of course, afunction of the speed of rotation of the balloon.

Instead of only one ring several such rings arranged in analogous mannermay be provided axially spaced the one above the other. Moreover, theelevated and recessed portions of the different axially spaced rings maybe angularly displaced, an arrangement which likewise has a favourableeffect upon the shape of the balloon.

FIG. 2. shows a different form of limiter 20 in which the inside edge ofthe ring 24 has a saw-tooth conformation. This limiter can be used onlyfor the control of a balloon travelling in the direction of rotationindicated by arrow 25. Otherwise, the ring functions in the manneralready described in detail with reference to -FIG. 1.

FIGS. 3 and 4 show polygonal rings inserted into the body 20 of theballoon limiter. Four hexagonal rings indicated by numerals '1 to 4 areaxially spaced. This arrangement of the rings, the one above the other,is readily seen in FIG. 4. Again the effect of the arrangement isanalogous to that already described with reference to FIG. 1.

Whereas in the forms of construction shown in FIGS. 1 to 4 rings withelevations and depressions are disposed concentrically around the centreaxis of the limiter, FIGS. 5 and 6 illustrate a limiter according to theinvention in which smooth rings are provided which are eccentricallypositioned in relation to the limiter axis. The several rings areindicated by reference numerals 11 to 18. The same reference numeralsare used in the drawing to indicate the respective specially markedcentres of the several rings, which are located on a helixconcentrically surrounding the limiter axis. The resultant overallformation of the limiter, illustratively represented in FIG. 6, impartsto the balloon formed by the travelling yarn a particular shape in whichthe yarn is supported only by specific sections of the several rings,which project well into the inside of the limiter, whereas the yarn willskip across those portions of the several rings which are locatedfurtherto the outside.

In the forms of construction shown in the drawings the inwardlyprojecting sections which impart kinetic impulses to the balloon areequidistantly distributed around its circumference. In particular casesit may be an advantage to distribute these sections in nonuniformmanner. The same applies to the relatively angularly staggeredelevations at different axial levels, which may likewise be irregularlypositioned.

What we claim is:

1. The method of reducing friction and yarn tension on balloon-formingtwist spindles, particularly on double twist spindles, which compriseslimiting the outer travel of the yarn in the balloon substantially fromthe zone at which the balloon is initiated and imparting inward periodicimpulses to the ballooning yarn at regularly spaced discrete zonesaround and in staggered order along the axial length of the balloonwhile the yarn is tending to centrifuge out to a maximum ballooningdiameter.

2. A balloon limiter on a balloon-forming twist spindle, particularly adouble twist spindle,-for limiting the outward travel of the yarn in theballoon from substantially the zone of initiation, said limiter havinginternally thereof a plurality of rings, the inner periphery of each ofwhich has inwardly extending slip surface sections which are adapted andarranged to impart periodic impulses to the ballooning yarn whilst thisis tending to ii. centrifuge outwards to a maximum diameter, said ringsbeing axially spaced from one another and the said inwardly extendingsections being relatively angularly staggered in one ring in relation toanother.

3. A balloon limiter on a balloon-forming twist spindle, particularly ona double twist spindle, for limiting the outward travel of the yarn inthe balloon from substantially the zone of its initiation, said limiterhaving internally thereof a plurality of axially spaced rings, which areplaced with their centres on an imaginary helix surrounding the axis ofthe limiter and adapted and arranged to impart inward kinetic impulsesto the ballooning yarn whilst this is tending to centrifuge outwards toa maxirnnm diameter.

References Cited in the file of this patent UNITED STATES PATENTS

1. THE METHOD OF REDUCING FRICTION AND YARN TENSION ON BALLOON-FORMINGTWIST SPINDLES, PARTICULARLY ON DOUBLE TWIST SPINDLES, WHICH COMPRISESLIMITING THE OUTER TRAVEL OF THE YARN IN THE BALLOON SUBSTANTIALLY FROMTHE ZONE AT WHICH THE BALLOON IS INITIATED AND IMPARTING INWARD PERIODICIMPULSES TO THE BALLOONING YARN AT REGULARLY SPACED DISCRETE ZONESAROUND AND IN STAGGERED ORDER ALONG THE AXIAL LENGTH OF THE BALLOONWHILE THE YARN IS TENDING TO CENTRIFUGE OUT TO A MAXIMUM BALLOONINGDIAMETER.
 2. A BALLOON LIMITER ON A BALLOON-FORMING TWIST SPINDLE,PARTICULARLY A DOUBLE TWIST SPINDLE, FOR LIMITING THE OUTWARD TRAVEL OFTHE YARN IN THE BALLOON FROM SUBSTANTIALLY THE ZONE OF INITIATION, SAIDLIMITER HAVING INTERNALLY THEREOF A PLURALITY OF RINGS, THE INNERPERIPHERY OF EACH OF WHICH HAS INWARDLY EXTENDING SLIP SURFACE SECTIONSWHICH ARE ADAPTED AND ARRANGED TO IMPART PERIODIC IMPULSES TO THEBALLOONING YARN WHILST THIS IS TENDING TO CENTRIFUGE OUTWARDS TO AMAXIMUM DIAMETER, SAID RINGS BEING AXIALLY SPACED FROM ONE ANOTHER ANDTHE SAID INWARDLY EXTENDING SECTIONS BEING RELATIVELY ANGULARLYSTAGGERED IN ONE RING IN RELATION TO ANOTHER.